1. Field of the Invention
The present invention relates generally to a Broadband Wireless Access (BWA) communication system, and more particularly to a system and a method for handover in a BWA communication system.
2. Description of the Related Art
In the next generation communication system, research is being performed to provide users with services having various Qualities of Service (QoSs) at a high transmission speed. To support such a high transmission speed, the next generation communication system has been developed to ensure mobility and QoS in a BWA communication system capable of performing high speed transmission such as a Wireless Local Area network (LAN) system and a Wireless Metropolitan Area network (MAN) system. A representative communication system of the next generation communication system is the Institute of Electrical and Electronics Engineers (IEEE) 802.16e communication system.
FIG. 1 is a block diagram schematically illustrating a conventional IEEE 802.16e communication system.
Referring to FIG. 1, the IEEE 802.16e communication system has a multi-cell structure. The IEEE 802.16e communication system has multi cells, e.g., a cell 100 and a cell 150. Further, the IEEE 802.16e communication system includes a Base Station (BS) 110 that controls the cell 100, a BS 140 that controls the cell 150, and a plurality of Mobile Stations (MSs), e.g., 111, 113, 130, 151, and 153. The transmission/reception of signals between the BSs 110 and 140 and the MSs 111, 113, 130, 151, and 153 is accomplished using a signal transmission/reception scheme such as an Orthogonal Frequency Division Multiplexing (OFDM) scheme or an Orthogonal Frequency Division Multiple Access (OFDMA) scheme. In FIG. 1, the MS 130 is located in a boundary region (or a handover region) between the cell 100 and the cell 150. Accordingly, the IEEE 802.16e communication system must support handover for the MS 130.
As described above, because the IEEE 802.16e communication system must support mobility of a MS, supporting handover for a MS is important for determining performance of the IEEE 802.16e communication system. That is, it is also necessary to accommodate handover for a MS between a plurality of BSs, handover between BSs in a multi-sector structure supporting a plurality of sectors, and inter-sector handover within the same BS. At the present time, the IEEE 802.16e communication system has proposed only extremely restricted handover processes to support handover for a MS. Accordingly, it is necessary to provide detailed handover processes to support handover for a MS.